I have since posted to the Castle Windsor development mailing list with a possible solution to this. I will add this into a valid answer when account restrictions are not in place.
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RossDec 19 '11 at 6:42

Yes, this is obviously a case of NHibernateIntegration not being updated for Windsor 3.
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Mauricio SchefferDec 19 '11 at 13:52

Yes, always send a patch. Never wait for confirmation. Be "pro-active" (stupid word I know, but it does apply here). Worst case, it gets rejected, but it probably won't.
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Mauricio SchefferDec 19 '11 at 22:46